Method of producing smokeless gunpowder



Patented Nov. 29, 1932 a nnenmusz Bamnwrcz-mzxxowsm AND a:

PABTYKA, OF BOGHACZEW,

METHOD OF PRODUCING SMOKEI-Efi emow m' Ho Drawing. Application filedJune 25, 1930, Serial No. 488,816, and in Yoland February 24,1987.

V 10 the gunpowder mass and the introduction of additional operationsdirectly after having pressed the gunpowder threads.

As is generally known carbine gunpowder,

' in order to burn progressively, must be made from gelatinizednitrocellulose and the surface of the gunpowder grains must be subjectedto an additional treatment for slower combustion in the chamber.Entirely different properties are r'equiredof sporting 2 and practicegunpowders. The combustion of these gunpowders must be very rapid, sothat even at small pressures in'the chamber (400-500 atmospheres in thecase of sporting guns) there will be complete combustion 1 when a shotis being fired.

The method according to the present invention provides the possibility,while using .11 only the machines ordinarily used for the manufacture ofcarbine gunpowder, (other 3 machines may also be used), of obtainingvery uniform sporting and practice gunpowders in the form ofexceedingly-thin-walled tubular threads, having an ideal combustion andany desired ballistic properties, which latter can be easily regulatedduring the process of production.

The walls of the tubular threads of powder prepared by our method have athickness of 0.030.1 mm., and powder tubes of such thin walls could-notbe obtained by the pressure usually employed hitherto with a pitch orthorn matrix, as every matrix would unavoidably be immediately blockedwith portions of the powder material.

The method according to the present invention is as follows. Explosivematerial is gelatinized by means of suitable solvents, such as,.forinstance, alcohol and ether, as in the case of progressive powders. Itis then extruded in the form of continuous the solvents used or of oneof the in vmay contain 0.1-0.5% of cylindrical threads having a diameterof 0.3-1.5 mm. according to the kind of powder, e. g. 0.8 mm., thethread formed containing solvent to an amount which varies between130-150% of the weight of the dry mass. The thread is then partly driedin order to" make it slightly stable; it may be dried,-'for example, tosuch an extent that it contains a wei ht of water which is not less thanthe weight of the original dry mass. The drying may, for example, becarried out by subjecting the thread to 50 C. for 1-2 minutes (or untilthe solvent content is 95-100% of the weight of the dry mass),preferably in a fluid, which may be the air. The thread thus obtains adried, somewhat hard, surfacef whilst the core-portion remains perfectlysoft, and it is then plunged into a fluid having a temperature (e. of45-80 C. according to the nature of t e powder) somewhat higher than theboiling point ofedients of extruded material. The fluid 1s chosen suchthat it does not act chemically upon the powder. The temperature of thefluid bath evaporates the solvent contained in the thread and createspresure from the centre of the thread towards the periphery, whichlatter, however, is relatively hard, and consequently a channel is blownthroughout the 80 length of the thread. Immersion in the bath lastsabout 10 to 25 minutes and the part1 dried threads are cut in the usualway, pro erably while still moist so as to eliminate danger ofexplosion. The cut grains are then dried, soaked, polished, graphited orcoated with camphor, centralite or other coating materials. Theexplosive material being latinized aplute for the purpose of increasingthe e ectrical conductivity. It may also contain 640% ofwater for thepurpose of obviatin the brittleness of the threads when forme Thestability of the material, also, may be increased by adding diphenlamine, urea derivatives, etc.

to the extent 0 04-12%.

The most suitable nitro-cellulose compound for carrying out this processcontains 12.713% of nitrogen. It is however possible 1 satisfactoril totransform by the process into practice an sporting powder nearl all oldpowders, such as rifle and gun pow er withdrawn from ordnance use orpowderwhich, owing to low stability, must be destroyed. The old powderor nitro-cellulose is incorporated with a mixture of alcohol and ether,acetone or other solvent in a quantity of 90-160%"by weight of the drymass with an addition of 0.1 to 0.5% of graphite and 4% to 10% of wateras well as 0.4 to 1.2% of stabilizin substance. The mass is kneaded in akneading apparatus for several hours and after extrusion the extrudedthreads are subjected to the hot fluid bath, as above described.

In the forcible evaporation of ether in the presence of oxygen and wateror steam, peroxides are easily formed, which have a gegative effect uponthe stability of the power. bath easily oxidized-substances which haveno such detrimental effect on the powder and which destroy the action ofthe peroxides (ea 0.1-1% of aniline, phenylurea, or nitrous or other,reducing' acids). When transforming old powders of reduced stability itis advisable to add 12% of substances which neutralize the acids (e. g.sodium hydrogen carbonate In view of the small thickness of the wall andthe cylindrical, tubular, form of the thread, the ignition velocity ofthe powder is high, it being well known that this -ve- I locity is afunction of the size of the grains.

What we claim is:

j 1. Method of manufacturing smokeless drical-shaped hardened exteriorleaving atubular-shaped thread, artially drying the tubular-shapedthread t as formed, cutting the partially dried threads'so as to formthinwalled tubular grains, drying, soaln'ng, pollshing and coating, asset forth.

2. Method of manufacturing smokeless practice and sporting powderconsisting in gelatinizing explosive material withalcohol 1 and either,extruding the gelatinized material I m the form of thin threads,superfically'drying the extrudedthreads,plungingthethreads in a fluidbath having a temperature above the boiling temperautre of. at least oneof the ingredients in the thread so that said ingredient evaporates andejects the explosive material contained in the cylindrical-shapedhardened exterior leaving a tubular-shaped It is therefore advisable toadd to the' 4 thread thus forme in an aqueous fluid bath at 458Qi C. sothat at least one of the ingredients evaporates and ejects the explosivematerial contained in the cylindrical-shaped hardened exterior leaving atubular-shaped thread, partially drying the tubular-shaped thread thusformed, cutting the partially dried threads so as to form thinwalledtubular grains, drying, soaking, polishing and coating, as set forth. 4.Method of manufacturing smokeless practice andsporting powder consistingin gelatinizing explosive material with alcohol and ether, extruding thegelatinized material in the form of threads of 0.3-1.5 mm. diameter,superficially drying the threads by heating at 50 C. for 12.minutes,plun 'ng the threads in an aqueous bath at,45 for 10-25 minutes so thatat least one of the ingredients evaporates and ejects the explosivematerial contained in the cylindrical-shaped hardened exterior leaving atubular-shaped thread, partially dr ing the tubular-shaped thread thusformed: cutting the partially dried threads so as to form thin-walledtubular grains, drying, soaking, polishing and coating, as set forth. 3

5. Method of manufacturing smokeless practice. and sporting powderconsisting in gelatinizing explosive ,material with alcohol and ether,extruding the gelatinized material in the form of threads, superficialldr g the-extruded threads, plunging the t rea s in an aqueousbath-containing a reducing agent at 45.80 C. so that at least one of theingredients evaporates and ejects the ex losive inaterial containedinthe cylindrical-shaped hardened exterior leaving a tubular-shapedthread, vpartially d g the tubular-shaped d cutting ;,the partiallydried threads so as to form thin-walled tubular grains, drying, soaking,polishing and coating, as set forth.

6. Method of manufacturing smokeless.

practice and sporting powder consistingrin. gelatinizing explosivevmaterial Withalcohol and ether, extruding the gelatinized material inthe form of threads, su erficially d the extruded threads, plunglng thethrea sin an aqueous fluid bath containing nitrous acid at 4580 (1., sothat atleast one of the ingredients evaporates and ejects the explosivemanesaees thread thus formed, cutting the partially dried threads so asto form thin-walled tubular grains, drying, soaking, polishing andcoatin as set forth. i y g 7, ethod of manufacturing smokeless practiceand sporting powder consisting in gelatinizing explosive material withgelat-inizing solvents in presence of (Ll-% of graphite, 640% of waterand 0.41.2% of urea derivative, extruding the gelatinized material inthe form of cylindrical threads, superficially drying the extrudedthreads, plunging the threads in a fluid bath having a temperature abovethe boiling tempera- 'tureof one of the ingredients in the thread sothat at least the said ingredient evaporates and ejects the explosivematerial contained in the cylindrical-shaped hardened exterior leaving atubular-shaped thread, partially drying the tubular-shaped thread thusformed, cutting the partially dried threads so as to form thin-walledtubular grains, drying. soaking, polishing and coating, as set forth.

8. Method of manufacturing smokeless practice and sporting powderconsisting in gelatinizing explosive material with gelatinizingsolvents, extruding the gelatinized material in the form of cylindricalthreads, superficially drying the extruded threads until they containsubstantially equal amounts by Weight of explosive material and the saidgelatinizing solvents, plunging the threads I in a fluid bath having atemperature above as the boiling temperature of at least one of theingredients in thethread so that said ingredient evaporates and ejectsthe explosive material contained in r the cylindrical-shaped hardenedexterior leaving a cylindricala shaped thread, partially drying thetubular shaped thread thus formed, cutting the par; tially driedthreads, soas to form thin-walled tubular grains, drying, soaking,polishing and coating as set forth.

;9. Method of manufacturing smokeless practice and sporting powderconsisting in *gelatinizing explosive material with alcohol andether,extruding-the gelatinized material in the form of threads,superficially drying 59 the extruded threads until the weight of alcoholand ether contained therein is substantially equal to the weight of thesaid explosive material, plunging the threads in an aqueous fluid bathat -80 C. so that at least one of 5a the ingredients evaporates andejects the explosive material contained in the cylindricalshapedhardened exterior leaving a tubularshapedthread, partially drying thetubularsha ed thread thus formed, cutting the partia y dried threads,drying, soaking, polishin and coating so as to form thin-walled tub arains, as set forth.

10. ethod of manufacturing smokeless practice and sporting powderconsisting .in gelatinizingexplosive material with alcohol and ether,extruding the gelatinized material in the form of threads, superficiallydrying the extruded threads until the weightof alcohol and ether thereinis substantially equal to the weight of explosive material, plunging thethreads in an aqueous bath containing a. reducing agent at 45-80 C. sothat at least one of the ingredients evaporates and ejects the explosivematerial contained in the tubular-shaped hardened exterior leaving atubular-shaped thread, partially drying the tubular-shaped thread thusform, cutting the partially dried threads so as to form thin-' walledtubular grains, drying, soaking, polishing and coating, as set forth.

11. Method .of. manufacturingsmokeless practice and sporting powderconsisting in gelatinizing explosive material with alcohol and ether,extruding the gelatinized material in the form of threads of 0.3-1.5 mm.diame ter, superficially drying the threads by heating at C. until theweight of alcohol and ether contained therein is substantially equal totheweight of the said explosive material, plunging the threads in anaqueous bath at 45-80 C. for 10-25 minutes so that at least one of theingredients evaporates and ejects the explosive material contained inthe cylindrical-shaped hardened exterior leaving a cylindrical-shapedthread, partially drying the tubular-shaped thread thus formed, cuttingthe partially dried threads, so as to form thin-walled tubular grains,drying, soaking, polishing and coating, as set forth. 12. Method ofmanufacturing smokeless practice and sporting powder consisting ingelatinizing explosive material with alcohol and ether, extruding thegelatinized material in the form of threads, superficially drying theextruded threads until the weight of alcohol and ether thereinissubstantially equal to the weightof the explosive material,

plunging the threads in an aqueous fluid bath containing nitrous acid at4580 C. so that at least one of the ingredients evaporates, and ejectsthe ex losive' material contained in the cylindricalaped hardenedexterior leaving a tubular-shaped thread, partially drying thetubular-shaped thread thus formed, cutting thepartially dried threads soas to form thinwalled tubular grains, drying, soaking, polishing andcoating, as set forth In testimony whereof we have signed our names tothis specification.

EUGENIUSIZ BAZYLEWlCZ-KNIAZYKOWSKI. KAZIMIERZ PAR'I'YKA.

